Digger tooth



March 20, 1934. v Q MEKEEL 1,951,988

DIGGER TOOTH Filed Dec. 30, 1931 2 Sheets-Sheet 1 March 20, 1934. v. c. MEKEEL DIGGER TOOTH Filed D60. 30. 1931 2 Sheets-Sheet 2 Patented Mar. 20, 1934 ELFNETEE STATES PATENT QFFE 4 Claims.

This invention relates to improvements in a digging tooth or more particularly a dipper tooth, and consists of the matters hereinafter described and pointed out in the appended claims.

The digging or dipper tooth, as shown herein, is of the two-part, reversible type, consisting of a point and of a base and is of the kind described in my pending application Serial Number 345,719 filed March 9th, 1929 now Patent No. 1,845,677; that is to say, it is a digging tooth including a part having a socket and a part having a slotted tenon engaged in said socket with means for expanding the tenon in the socket to lock the two parts together.

The object of the present invention is to provide a novel and improved form of tenon and socket which is of simple and economical construction as well as efficient in operation, and to provide an improved means for presenting the 2 thrust bearing between the two parts which will insure rigid engagement therebetween under all conditions of wear. Another object of the invention is to provide a construction in which the pin for expanding the tenon in the socket may be inserted from the same side, the top side, when the point is reversed.

The advantages of the invention will appear as I proceed with my specification.

In the drawings:-

Figure 1 is a perspective view of one part of my novel digging tooth, in this case the base, partially broken away to show the interior form of the socket.

Figure 2 is a'perspective View of the associated part, in this case the point, with the tenon for engagement in the socket of the first mentioned part.

Figure 3 is a perspective view of the pin for expanding the tenon in the socket.

Figure 4 is a longitudinal central section through the two parts of the digging tooth in assembled relation in a plane at right angles to the edge of the point.

Figure 5 is a view representing a transverse section in a plane indicated by the line 55 of Figure 4.

Figure 6 is a longitudinal section in a plane indicated by the line 66 of Figure 4.

Referring now to that embodiment of my in- 50 vention illustrated in the drawings:10 indicates the socket part of the assembly, in this case the base, and 11 indicates the part with the tenon, in this case the point. The point as shown is of the usual wedge-shaped section and is reversible. 12 indicates the tenon projecting rearwardly from the body of the point. Said tenon is approximately rectangular in cross section, as shown in Figure 5, and is slotted as indicated at 13. Said slot is enlarged near the end of the tenon and is formed to provide a keyway 14. 15 indicates the socket in the base. Said socket is similar in cross section to the cross section of the tenon 12, which it is adapted to receive, and opens through the nose of the base, as shown in Figure 1.

The point 11 is provided at either side of the planes of the vertical faces of the tenon 12 with recesses 16. Said recesses have top and bottom faces 17, 17 which converge towards the edge of the point. The base is provided with nibs or projections 18, 18 which likewise have faces 19, 19 which converge towards the point 11 and are adapted to have fiat contact with the faces 1'7, 17 of the recesses in the point when the point and base are in assembled relation. The projections 18 on the base are reduced in vertical width adjacent the nose of the base so that top and bottom shoulders 20, 20 are formed at the top and bottom of said projections. The angle of the converging engaging faces 17, 17 and 19, 19 of the point and base are so designed that when the tenon 12 is completely inserted into the socket 15 in the base, the ends 21 of the projections or nibs 18 terminate short of the bottoms 22 of the recesses 16 in the point and the rear end 23 of the point is spaced from the shoulders 20 on the base. Thus the thrust engagement between the base and point,that is to say, between the two parts of the digging tooth, is provided entirely by the engagement of the faces 17 and 19, respectively, of the recesses 16 in the point and of the nibs or projections 18 of the base. By this means any wear on the contacting parts will be taken up and compensated for by further driving the tooth towards the base with no possibility of the shoulders 20 or the ends of the projections 18 engaging and thereby limiting that movement.

To accommodate and permit the aforesaid movement, the socket 15 of the base and the tenon 12 of the point are formed as follows:- As shown herein the top and bottom walls 24, 24 of the socket in the base and the top and bottom faces 25 of the tenon are made parallel and fiat. The side walls 26, 26 of the socket are made transversely slightly concave and the side faces 2'7, 27 of the tenon are made transversely slightly convex, as shown in Figure 5. Such formation is readily provided by making each of said walls and faces in two difierent planes which intersect in a longitudinal median line in the wall or face as the case may be. (See Figure 5.) At said longitudinal median lines, longitudinally extending grooves 28 are preferably formed 5 in the side walls 26, 26 of the socket for convenienee in casting so that no inequalities of metal will be left or formed at or in the neighborhood or said lines.

The tenon 12 is formed of uniform cross section throughout its length. The socket 15 is of similar cross section except the concaved side walls, without changing their degree of concave ity, diverge slightly as the socket 15 progresses from the projections 18 rearwardly to near the sockets extremity, as shown in Figure 6, where it appears to an exaggerated degree for purposes of illustration. As a result, the tenon is readily inserted into the socket, being entirely free of engagement with the top and bottom walls of 'he socket, and loosely engaging the side walls of the socket, particularly at its rearward extremity. When the tenon is expanded in the socket, the relative concave-convex formation of the tenon and socket as well as the diverging conoavo-oonvex relation of the two parts when the tenon is expanded, act to lock the two parts against extraction as well as against rotative or rocking movement about a transverse axis of the tenon, notwithstanding there is no engageso'finent between the tenon and socke on the top and bottom faces thereof. And this construction, as will be obvious, permits the tenon, although expanded, to be forced further home in the socket under the stress of digging in case of wear or inequalities between the engaging faces of the projections 18 and the recesses 16, and reset to positive union by the means provided in further expanding the tenon.

29 indicates the pin for expanding the tenon in its socket. Said pin is tapered, as clearly shown in Figures i and 5. The keyway 14 in the tenon is tapered from top and bottom toa transverse median plane of the tenon. As a result the pin may be inserted for expanding the tenon from either the top or the bottom side of said tenon, so that when the tooth is reversed and that side of the tenon which was on the bottom in the first place is brought to position to become the top side of the tenon, the pin soinlay be inserted into the keyway and expanded therein from the top side of the tooth. This has been for-"id to be a great convenience when reversing the tooth. The is slotted, as indicated at so so that it may be slightly expanded to lock it in the keyway.

As will. be understood, the top and bottom of the part having the socket, in this case the base, is provided with aligned apertures 18a for the insertion of the pin from top or bottom. Said apertures are of sufficient diameter to permit ready insertion of said pin without engagement with the base or other part having the socket.

i claim as my invention:

in a inulti-pait digging tooth, a part ha ing a socket, a part having a slotted tenon adapted to engage in saic socket, a keyway in said slotted tenon, said keyway converging from top and bottom of the tenon towards a median plane, and a tapered pin adapted to be engaged in said keyway for expanding said tenon and capable of insertion from either end of said keyway.

2. In a muiti-part digging tooth, a part having a socket, a part having a slotted tenon of slightly less depth than that of said socket adapted to engage in said socket, said tenon and socket each having top and bottom substantially fiat parallel walls, said socket having transversely convex side v alls slightly diverging continuously from its outer end to permit the free longitudinal movement of said tenon into said socket, said 'enon having side walls which are transversely convex and complementary to the side walls or" said socket and extend in parallel relation to the plane of operation of said digging tooth, and means for expanding said tenon in said socket to engage the convex sides of said tenon with the concave sides of said socket throughout the length of said tenon to oppose any tendency of the digging tooth to yield in operation about an axis normal to its plane of operation.

3. In a multhpart digging teeth, a part having a socket, a part having a slotted tenon of slightly less depth than that of said socket adapted to engage in said socket, said tenon and socket each having top and bottom substantially flat parallel walls, said socket having transversely convex side walls slightly diverging continuously iron. outer end to permit the free longitudinal movement of said tenon into said socket, said tenon having side walls which are transversely convex and complementary to side walls or" said socket and extend in parallel relation to the p one of operation of said digging tooth, and a pin adapted for engagement in said slotted tenon to force the convex sides of said tenon into rigid engagement wtih the concave sides of said socket throughout the length of said tenon to oppose any tendency of the digging tooth to yield in operation about an axis normal to its plane of operation.

4. In a multi-part digging tooth, part having a socket, a part having a slotted tenon of slightly depth than that of said socket adapted to engage in said socket, said socket having transversely convex side walls slightly diverging continuously from its outer end to permit the free longitudinal movement or" said tenon into said socket, said tenon having side walls which are transversely convex and complementary to the side walls of said socket and extend in parallel relation to the plane of operation of said digging tooth, the socket part having projections and the tenon part having recesses to receive said projections, said projections and recesses having converging faces which provide the sole thrust engagement between said two parts, and means for expanding said tenon in said socket to engage the convex sides of said tenon with the concave sides of said socket throughout the length of said tenon to oppose any tendency of the digging tooth to yield about an axis normal to its plane of operation.

VAN CORTRIGHT MEKEEL. 

